Invert the blobs found from OpenCV

advanced
#1

Hi everyone,

I’m working on a triangulation program that pulls blobs from video and triangulates the contour points. I’m stuck on one issue, though. I’m trying to invert the blobs so that I triangulate the points from outside of the contours, rather than the inside. I tried messing around with the ofxCvImage invert() function but I don’t think it’s exactly what I’m looking for.

Any suggestions?

Thanks,
Ian

#2

Ian,

Have you tried inverting the pixels you detected from the camera? Perhaps if you made every black pixel white and vice versa you’d get the blobs you wanted.

http://opencv.wikispaces.com/4)+Inverting+the+Image

Apologies I don’t have a more thorough code example, if I get a chance I’ll post one up.

#3

Yes I have, using the invert() function on the grayscale difference image. Unfortunately, opencv seems to still pick up the same blobs, even when they are black. I also tried messing around with the blob minimum area but it didn’t affect anything.